drm: fix setversion ioctl zeroing

Egbert Eich reported a bug 2673 on bugs.freedesktop.org and tracked it
down to a missing memset in the setversion ioctl, this causes X server
crashes so I would like to see the fix in a 2.6.11.x tree if possible..

From: Egbert Eich <eich@pdx.freedesktop.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/drm_ioctl.c

@@ -326,6 +326,8 @@ int drm_setversion(DRM_IOCTL_ARGS)
 
 	DRM_COPY_FROM_USER_IOCTL(sv, argp, sizeof(sv));
 
+	memset(&version, 0, sizeof(version));
+
 	dev->driver->version(&version);
 	retv.drm_di_major = DRM_IF_MAJOR;
 	retv.drm_di_minor = DRM_IF_MINOR;